The invention relates to stays for fitting to stayed bridges where they connect the towers of such bridges to their decks, which stays are constituted by multiple strands juxtaposed side by side, with each of the strands itself preferably being of the "individually protected" type, i.e. constituted by a bundle of metal wires that are parallel or twisted together and that are received in a continuous sheath together with an interposed protective substance.
More particularly, the invention relates to methods and apparatuses for mounting stays of the kind in question in their final oblique configurations in which the stays together make up sheets, generally vertical sheets, disposed on either side of each tower.
More particularly, the invention relates to the case where at least some of the stays to be mounted are very long, which length may exceed 200 meters.
Under such circumstances, it is hardly possible to implement the known technique of making up a complete stay horizontally at the foot of the tower which is to support it, and then raising the end of said stay that is located adjacent to the tower by pulling on the stay, given that the weight of the stay is too great.
Another known technique for mounting stays of the kind in question consists in using a cableway type system to pull said stay obliquely along its axis after the stay has already been made up, i.e. after its component strands have been juxtaposed side by side.
For this purpose, a carrier cable is initially suspended between a high point of the support tower and the deck, and a fastening member having the head or top end of the stay coupled thereto is caused to run along said cable by means of suitable running gear.
Prior installation of such a carrier cable is itself an operation that is difficult and expensive, and in this case also, the forces brought into play when pulling on the stay become prohibitive for very great lengths.
The invention seeks, above all, to remedy those various difficulties.